(1) Field of the Invention
This invention relates to a multi-chip-package for active and/or passive devices. The devices are joined to a flexible tape which is then joined to a substrate having a cavity such that the devices are within the cavity.
(2) Description of the Related Art
Ultra Large Scale Integration, ULSI, packaging is discussed in a book by C. Y. Chang and S. M. Sze entitled "ULSI Technology", 1996, The McGraw-Hill Companies, Inc., pages 573-582.
U.S. Pat. No. 5,150,274 to Okada et al. describes a multi-channel module with a plurality of chips mounded on a multilayer circuit board.
U.S. Pat. No. 5,620,928 to Lee et al. shows an ultra thin ball grid array using a flex tape or printed wiring board.
U.S. Pat. No. 5,648,679 to Chillara et al. describes a dielectric flex tape substrate defining a predetermined array of electrically conductive traces and an array of solder balls or solder columns electrically connected to the bottom surface of the flex tape substrate and the traces. An integrated circuit chip having a series of input/output pads is supported on the substrate.
U.S. Pat. No. 5,602,419 to Takeda et al. describes a chip carrier semiconductor device comprising a semiconductor chip having a surface on which a plurality of contact pads, a tape carrier overlying the semiconductor chip and a plurality of leads provided on the tape carrier overlying the semiconductor chip.
U.S. Pat. No. 5,239,448 to Perkins et al. describes the formation of multichip modules. The invention shows a multichip module carrier that is constructed on a flex carrier, along with other components to form a subsystem.
U.S. Pat. No. 5,147,210 to Patterson et al. describes a first pattern of electrical conductors on a first electrical component and a second pattern of electrical conductors on a second electrical component.
A paper by A. Aintila et al. entitled "Electroless Ni/Au Bumps for Flipchip-on-Flex and TAB Applications", 1994 IEEE/CMPT Int'l Electronics Manufacturing Technology Symposium, pages 160-164 describes an electroless Ni/Au wafer bumping process.
A paper by R. W. Johnson et al. entitled "Adhesive Based, Flip Chip Technology for Assembly on Polyimide Flex Substrates", 1997 International Conference on Multichip Modules, pages 81-86 describes research conducted to develop and evaluate isotropically conductive adhesive preforms.
A paper by P. Elenius entitled "Flex on Cap-Solder Paste Bumping", 1997 International Symposium on Advanced Packaging Materials, pages 115-116 describes the capabilities and reliability results of the Flex on Cap solder bumping process.
A paper by R. Aschenbrenner et al. entitled "Flip Chip Attachment Using Anisotropic Conductive Adhesives and Electroless Nickel Bumps", 1996 IEEE/CMPT Int'l Electronics Manufacturing Technology Symposium, pages 26-33 describes studies carried out on electrical and mechanical performance of two types of anisotropic adhesives.
A paper by A. F. J. Baggerman et al. entitled "Reliable Au--Sn Flip Chip Bonding on Flexible Prints", 0569-5503/94/0000-0900 1994 IEEE, 1994 pages 900-905 describes Au--Sn flip chip bonding of integrated circuit chips on flexible polyimide prints.
A paper by C. S. Milkovich et al. entitled "Double Sided Flexible Carrier with Discretes and Thermally Enhanced FCA/COF", 0569-5503/93/0000-0016 1993 IEEE, 1993, pages 16-21 describes an electronic assembly using SMT components, wire bonded chips as well as area array chips attached to a flexible carrier.